Tool for shortening watch band spring bars



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TOOL FOR SHORTENING WATCH BAND SPRING BOARS Filed Aug. 12, 1955 /6 /7 30 Z9 Za /9 Z/ ATTE/VEYS United States Patent Oi TOOL FOR SHORTENING WATCH BAND SPRING BARS.

Perry L. Lamm, Wilson, N. C. Application August 12, 1955, Serial No. 528,029

2 Claims. (Cl. 81-6) The present invention relates to watchmakers tools and in particular to a tool for shortening the barrel of a watch band spring bar without disturbing the bearing pin of the bar.

An object of the present invention is to provide a tool for shortening the barrel of a watch band spring bar without disturbing the bearing pin of the bar which can be used with a spring bar having just the bearing pin projecting from its ends and also withspring bars having bearing pins provided with llanges or collars which also project from the barrel of the bar.

Another object of the present invention is to provide a tool for shortening the barrel of a watch band spring bar without disturbing the bearing pin of the bar which is simple in structure, sturdily constructed, one which is economical to manufacture and assemble, and one which is highly effective in action.

These and other objects and advantages of the present invention will be fully apparent from the following description when taken in connection with the annexed drawing, in which:

Figure 1 is an elevational view of a portion of a watchmakers lathe with a spring bar supported in the chuck of the lathe and with the tool of the present invention in working position to sever the barrel ofthe spring bar with the means for holding the bearing pin of the spring bar in a position withdrawn from the bearing pin,

Figure 2 is a top plan view,

Figure 3 is an end view greatly enlarged taken on the line 3--3 of Figure 1,

Figure 4 is a sectional view greatly enlarged taken on the line 4-4 of Figure 1,

Figure 5 is a further sectional View greatly enlarged taken on the line 5-5 of Figure 1,

Figure 6 is a sectional View greatly enlarged taken on the line 6--6 of Figure 4, and

Figure 7 is a sectional view greatly enlarged of a spring bar with which the present tool may be used.

Referring in greater detail to the drawing in which like numerals indicate like parts throughout the several views, the tool of the` present invention is intended for use by watchmakers and watch repairmen to shorten the barrel of a watch band spring bar withoutdisturbing the bearing pin of the spring bar which projects from one end of the spring bar and comprises a pair of arms 10 and 11 arranged in face to face relation and connected by their one ends 12 for movement toward and away from each other. The other ends of each of the arms 10 and 11 are inwardly turned to provide a pair of cutting elements 13 and 14 adapted to embracingly engage and sever the barrel 15 of a watch band spring bar 16 along the line of engagement of the cutting elements 13 and 14 with the barrel 15. A holding member 17 extends longitudinally of the arm 10 intermediate its end and is connected to the arm 10 for longitudinal back-and-forth movement.

The front face 18 of the holding member 17 is provided with an inwardly-extending recess 19 of a configuration to conformably receive the projecting spring bar bearing pin 20 of the watch band spring bar 16 while the barrel 15 of the spring bar 16 is being severed along its line of embracing engagement with the cooperating cutting elements 13 and 14. The front face 18 of the holding member 17 also is provided with a second and counter-sunk recess 21 of a configuration to conformably'receive a spring bar bearing pin such as is shown in Figure 7 and indicated by the referenuce nluneral 22, the pin of this type of spring bar 16 having a flange or collar 23 projecting -from the one end thereof adjacent the portion to be severed.

Actuating means is provided for effecting by hand the back-and-forth movement of the holding member 17 so as to move the holding member 17 to the position where one of its recesses 19 or 21 may receive the bearing pin of the watch band spring bar to be severed and to press the bearing pin back within the barrel of the spring bar so that the cutting elements 13 and 14 will not engage or sever or otherwise disturb either the bearing pin or the shoulder or collar which may be a portion of the bearing pin. Specifically, the actuating means consists in a raised projection 24 secured to the holding member 17 and extending through a slot 25 in the one arm 10 and having a knurled upper surface so that the thumb or iinger of the user may engage it to move it toward and away from the cutting elements 13 and 14.

In use, the watch band spring bar Iwhich is to be shortened is mounted by one end for rotation in the chuck 26 of a watchmakers lathe 27 and the tool of the present invention is positioned with its cutting elements 13 and 14 embracingly engaging the portion of the barrel of the spring bar to be severed. The holding member 17 is moved toward the portion of the spring bar to be severed and serves to engage and support the pin 20 or 22 of the spring bar 16 or 16', respectively, in the recess 19 or 21, respectively. The face 18 of the holding member 17 serves as a gauge to measure the portion of the barrel to be removed, such a portion of the barrel being shown in Figure 7 after removal and indicated by the reference numeral 28. The cutting elements 13 and 14 are curved on their cutting edges as seen in Figure 3 and are also shaped so as to burnish the cut end of the barrel over the base of the pin 20 or 22 as indicated by the reference numeral 29 in Figure 7, after the arms 1t) and 11 have been moved together to sever the barrel of the rotating spring bar. The burnishing of the barrel prevents the outward movement of the pin 20 or 22 as a result of the biasing action of the spring within the barrel of the spring bar, the spring being indicated by the reference numeral 31B in Figure 7.

The tool of the present invention enables the watchmaker or Watch repairman to keep in stock a few sizes of spring bars for the repair of watch bands without keeping in stock a watch band spring bar of every length necessary to repair the watch bands presently in use. Intermediate sizes between a series of stock sizes may be readily obtained by the use of the tool of the present invention to shorten the barrel of a stock spring bar slightly longer in length than the one desired.

What is claimed is:

1. A tool for shortening the barrel of a watch band spring bar without disturbing the spring-biased bearing pin projecting from one end thereof comprising a pair offace of said holding member being provided' with an inwardly-extending recess of a conguration to conformably receive the projecting spring-biased bearing pin of the Watch band spring bar while the barrel of said bar is being severed along its line of embracing engagementwith said cooperating cutting elements.

2. A tool for shortening the barrel of a watch band spring bar Without disturbing the spring biased bearing pin projecting from one end thereof comprising a. pair of arms arranged in face to face relation and connected at one end for movement toward and away from each other, cooperating cutting elements on the' other end of said arms adapted to embracingly engage and sever the barrel of a watch bandspring bar along the line of engagement, a holding member extending longitudinally of oneo said arms' intermediate its ends and connected t'o said one arm for longitudinal back-and-forth sliding movement, the front face of said holding member being provided with an inwardly-extending recess of a configuration to conformably receive the projecting spring-biased bearing pin of the watch band spring bar while the barrel of said bar is being severed along its line of embracing engagement with said cooperating cutting elements, and hand-actuable means carried by said holding member for effecting the longitudinal movement of the latter.

References Cited in the file of this patent UNITED STATES PATENTS 1,857,731 Lund May l0, 1932 

